<uses-permission>

Note: In some cases, the permissions that you request
through <uses-permission> can affect how
your application is filtered by Google Play.

If you request a hardware-related permission —
CAMERA, for example — Google Play assumes that your
application requires the underlying hardware feature and filters the application
from devices that do not offer it.

To control filtering, always explicitly declare
hardware features in <uses-feature> elements, rather than
relying on Google Play to "discover" the requirements in
<uses-permission> elements. Then, if you want to disable
filtering for a particular feature, you can add a
android:required="false" attribute to the
<uses-feature> declaration.

For a list of permissions that imply
hardware features, see the documentation for the <uses-feature> element.

Specifies a system permission that the user must grant in order for
the app to operate correctly. Permissions are granted by the user when the
application is installed (on devices running Android 5.1 and lower) or while the app is running (on devices running Android 6.0 and higher).

The highest API level at which this permission should be granted to your app.
Setting this attribute is useful if the permission your app requires is no longer needed beginning
at a certain API level.

For example, beginning with Android 4.4 (API level 19), it's no longer necessary for your app
to request the WRITE_EXTERNAL_STORAGE permission when your
app wants to write to its own application-specific directories on external storage (the directories
provided by getExternalFilesDir()). However,
the permission is required for API level 18 and lower. So you can declare that this
permission is needed only up to API level 18 with a declaration such as this: